The present invention relates to a tire building drum with turn-up apparatus for building an unvulcanized tire with tire components of rubber or having reinforcement cords and two bead cores with high bead filling strips, said tire building drum having a central axis, two ring segments placed around the axis and spaced from each other each to support a bead core, drum segments placed around the axis and on the outside of each of the ring segments, which drum segments define a cylindrical surface to support tire components, means to radially expand that part of the tire components which is situated between the ring segments, the tire building drum having on both sides outside the ring segments a first set of axially extending, hingeable arms, each arm having an end directed at the ring segment, said end having a roller, means to axially and radially move each first set of arms from a first position in which the rollers of a first set of arms form a virtually closed ring to a second position in order to press the expanded part of the tire components which is situated between the ring segments to the part of the tire components which is situated outside the ring segments.
Such a tire building drum with turn-up apparatus is already known from British patent specification 1.532.960. This known tire building drum comprises two sets of arms, one set on one side outside of the ring segments and the other set on the other side outside of the ring segments. When moving the arms from the first position to the second position, rollers are brought at a greater distance from the axis, as a result of which the rollers are distanced from each other and thus do not form a virtually closed ring any more. Because the second position is a little distance further from the central axis of the tire building drum than the first position, the part of the tire components situated outside the ring segments is not fully pressed over the total height to the part of the tire components situated between the ring segments, and furthermore the ends of the arms come to stand at a distance from each other so that an incomplete circumferential pressure by the rollers is obtained. In order to prevent an incomplete attachment of the tire components, which may be detrimental to the quality of the tire to be produced, a sleeve of rubber is applied around the arms. Such a sleeve of rubber however, has a limited life span.